Clutch for IC engine cooling fan auxiliary drive - uses temp. sensitive snap disc in cooling water to determine position

摘要

The clutch is a friction unit (3) embodied into a conventional pulley (2) drive. The clutch is operated by rods (25) fixed to a diaphragm (5). An axially held (16) tube (7) from this diaphragm terminates inside a capped double sleeve (6) projecting from the water pump hub (14). A temp. sensitive snap disc (8) sets this sleeve so that either holes (19) in the tube admit pump discharge pressure to both sides (9, 10) of the diaphragm, or these are covered and others, in tube (20 and sleeve (21), lined up to connect the clutch side (10) to pump suction instead.